Sensitivity Analysis of a Single-Moment Microphysics Scheme to Changes in its Configuration

Abstract In order to determine the sensitivity of the rain generated by the microphysics scheme to changes in its configuration and select the changes with the greatest potential in reducing precipitation, this research was conducted. The Kinematic Driver model, a platform to isolate the microphysics of the complex interactions that take place in weather and climate models, was used to simulate hypothetical situations in the atmosphere. The influence of varying the rates of microphysics processes, as well as the effect produced by different methods to estimate the autoconversion and the intercept of rain size distribution, was analyzed. Variations in the cloud droplet concentration and in the cloud ice-snow ratio were also tested. The cloud water collection by raindrops was the most influential process in the generation of precipitation, it allowed to remarkably decrease the rain generated by both warm and mixed-phase clouds. In addition, some changes in methods to estimate the autoconversion rate and the intercept of the rain size distribution, as well as in the concentration of cloud droplets have shown potential in reducing the rain.